1. Field of the Invention
The present invention relates to a hydrogen generator which generates hydrogen from a compound containing hydrogen atoms.
2. Description of the Related Art
When using hydrogen as fuel in a fuel cell etc. for vehicular use, it is difficult to mount a hydrogen storage tank in the vehicle since the storage volume of hydrogen is extremely large. Therefore, it has been proposed to mount a hydrogen generator for generating hydrogen from hydrocarbon fuel in the vehicle (see Japanese Patent Publication (A) No. 2009-179504).
This hydrogen generator is provided with an upstream side oxidation unit and a downstream side decomposition unit. By running a mixed gas of a compound containing hydrogen atoms such as hydrocarbons and air into it, the generator burns part of the compound in the oxidation unit using oxygen in the mixed gas to generate heat of combustion, utilizes this heat of combustion to break down part of the compound in the decomposition unit to generate hydrogen, and discharges reformed gas containing hydrogen.
As related art, there is Japanese Patent Publication (A) No. 2009-179504.
In the hydrogen generator, it is necessary to make the flow rate of the reformed gas discharged from the hydrogen generator the desired flow rate and also to make the hydrogen concentration in the reformed gas the desired concentration. For this reason, the hydrogen generator simultaneously controls the flow rates of the compound and the air which form the mixed gas flowing into the hydrogen generator. However, sometimes the intended flow rate of the compound or the intended flow rate of the air in the mixed gas flowing into the hydrogen generator are not realized. In this case, the hydrogen concentration in the reformed gas cannot be made the desired concentration.